Nuclear magnetic resonance (NMR) is a physical phenomenon involving quantum mechanical magnetic properties of atomic nuclei in the presence of an applied, external magnetic field. NMR phenomena can be observed with an NMR spectrometer and used to study molecular physics, crystalline and non-crystalline materials. In particular, nuclear spin phenomena can be used to generate a spectrum comprised of a pattern of lines representing the various spins and spin interactions.
In order to perform an NMR measurement, the instrument must be set up to perform a particular measurement. A sample to be measured must be prepared, inserted into the instrument and a measurement run. The resulting intensity signals must then be processed to generate a spectrum. Finally, the spectrum must be interpreted in order to determine the composition of the sample.
Conventional automation software can be used to control the NMR spectrometer to perform routine measurements and signal processing software is available to process the intensity signals in order to generate an NMR spectrum. However, in order to produce accurate results, the spectrometer must be checked and calibrated. Further, the interpretation of the NMR spectrum is complex process requiring training and experience and a thorough knowledge of the compounds that may be present in the sample. For example, the NMR spectrum may include intensity signals from one or more compounds of interest, the solvent used to dissolve the sample and impurities in the sample and solvent. Consequently, NMR spectrometers are generally maintained and operated by highly trained laboratory scientists known as NMR spectroscopists.
In many production facilities, it would be desirable to make NMR measurements routinely on samples, such as raw materials without having NMR spectroscopists on staff. Often these measurements are simple pass fail measurements. Nonetheless such measurements made on conventional NMR spectrometers still require the training and knowledge of an NMR spectroscopist to perform the measurement and interpret the result.